KR20110037207A - Thermoplastic resin composition with excellent weatherability and a method for preparing thereof - Google Patents

Abstract

PURPOSE: A thermoplastic resin composition with excellent weather resistance is provided to secure impact resistance and rigidity by modifying a grafted ABS through hydrogenation reaction. CONSTITUTION: A thermoplastic resin composition with excellent weather resistance comprises 20-40 parts by weight of a core-shell graft-copolymer and 60-80 parts by weight of two kinds of styrene-acrylonitrile resin. The core-shell graft-copolymer is modified by adding hydrazine, peroxide-based compound and acid catalyst thereto and then performing hydrogen addition. The styrene-acrylonitrile resin has the content of acrylonitrile 20-33%, average molecular weight of 100,000 - 180,000, and glass transition temperature of 60 °C or greater.

Description

Thermoplastic resin composition excellent in weatherability and its manufacturing method {THERMOPLASTIC RESIN COMPOSITION WITH EXCELLENT WEATHERABILITY AND A METHOD FOR PREPARING THEREOF}

The present invention relates to a thermoplastic resin composition having excellent weather resistance and a method of manufacturing the same, and more particularly, to a conjugated diene rubber latex core, a hydrogenated core-shell graft copolymer including a hydrazine, a peroxide compound, and an acid catalyst. The present invention relates to a thermoplastic resin composition having excellent impact resistance, strength and weather resistance, comprising a styrene-acrylonitrile resin, and a method for producing the same.

ABS resin based on conjugated diene rubber is processed into a desired form through extrusion and injection of styrene-acrylonitrile copolymer prepared by emulsion polymerization and powder prepared by solution polymerization. General ABS resins are widely used in interior and exterior parts of electric and electronic products, automobiles and small toys, furniture, and building materials because of excellent processability, mechanical properties, and appearance properties.

However, the weather resistance is poor due to the double bond of butadiene rubber component used as an impact modifier. Double bonds are easily oxidized and discolored because they are easily broken due to the small amount of energy required to break one chain compared to a single bond. Therefore, ABS has a change in the appearance and color of the resin and the mechanical properties are drastically deteriorated in the environment where UV rays are directly received, such as outdoors. As mentioned above, the deterioration of this ABS resin is caused by the butadiene component, and hydrogen of -CH ₂ -adjacent to the remaining double bond in the molecule becomes the starting point of the oxidation reaction by the action of light or oxygen, causing the main chain to cause crosslinking reaction. Because.

In order to make the resin balanced by adding weather resistance while maintaining the excellent properties of the ABS resin, a method of adding a UV stabilizer, coating, plating, and the like is usually taken, but it is not an essential improvement. Here, various resins have been developed in which a butadiene component, which is a cause of deterioration, is removed and replaced with a rubber having no unsaturated bond. Representative resins include ABA resin using acrylic rubber instead of butadiene rubber and AES resin using EPDM rubber. However, since there is a tendency to be inferior to ABS in the manufacturing process or the basic physical properties, there is still a study to improve the weather resistance of ABS resin using a method of adding an additive to ABS.

Stabilizer formulations for improving the thermal stability of ABS resins are also well represented in the international application PCT / EP / 2003/008189. In the polymerization, it is disclosed to improve thermal stability by combining a primary antioxidant, an organic phosphite and a benzofuranone derivative as an antioxidant, and US Pat. No. 6,752,226 discloses an improvement in discoloration by combining a dioxopiperazine derivative. It is starting. In addition, Korean Patent Publication No. 10-2007- 0047073 discloses a first phosphite-based antioxidant in a base resin composed of acrylonitrile-butadiene-styrene copolymer (g-ABS) resin and styrene-acrylonitrile (SAN) resin. The present invention relates to a thermoplastic resin composition having improved thermal stability, initial photochromic resistance, and weather resistance, including a first phosphite antioxidant and a second phosphite antioxidant and an alkali metal phosphate having different temperature ranges of the oxidation reaction. However, the improvement of weather resistance due to the addition of such additives and the improvement of weather resistance due to the combination change occur as a major factor of the cost increase, and when additives are ejected into the gas during processing such as injection molding, impurities may appear on the surface of the molded article. It has a tendency to damage the product value of the molded article because it has a tendency.

Accordingly, US Patent No. 4,452,950 discloses that the oxidation and deterioration prevention properties are improved through hydrogenation of nitrile-butadiene rubber (NBR) latex using hydrazine and hydrogen peroxide. However, this also does not help to improve the weather resistance and discoloration resistance.

In order to solve the problems of the prior art as described above, the inventors of the present invention, in the preparation of the thermoplastic resin composition, using a hydrazine and a peroxide-based compound and an acid catalyst in the conjugated diene-based rubber latex core is modified through a hydrogenation reaction, When properly mixed with two styrene-acrylonitrile resin mixtures having different molecular weights, it is confirmed that the weather resistance is remarkably improved without lowering impact strength, tensile strength, and flexural strength as shown in the following Examples. Based on this, the present invention has been completed.

That is, an object of the present invention is to modify the core-shell graft copolymer based on the conjugated diene-based rubber latex core by hydrogenation, and to formulate a suitable styrene-acrylonitrile resin therein to provide impact resistance, rigidity and weather resistance. It is an object to provide this excellent thermoplastic resin composition and its production method.

In order to achieve the above object, the present invention

a) A hydrazine, a peroxide-based compound and an acid catalyst are added to a core-shell graft copolymer in which an aromatic vinyl compound and a vinyl cyan compound are grafted to a conjugated diene rubber latex core having an average particle diameter of 200 to 500 nm, and hydrogen 20 to 40 parts by weight of the addition modified core-shell graft copolymer, and

b) 60 to 80 parts by weight of two styrene-acrylonitrile (SAN) resins having an acrylonitrile content of 20 to 33% and a weight average molecular weight of 100,000 to 180,000.

In addition,

A first step of preparing a core-shell graft copolymer in which an aromatic vinyl compound and a vinyl cyan compound are grafted to a conjugated diene rubber latex core having an average particle diameter of 200 to 500 nm;

Adding a hydrazine, a peroxide-based compound and an acid catalyst to the core-shell graft copolymer to obtain a hydrogenated core-shell graft copolymer; And

Two styrene-acrylonitriles having an acrylonitrile content of 20 to 33% as a remainder in the hydrogenated core-shell graft copolymer, a weight average molecular weight in the range of 100,000 to 180,000, and a glass transition temperature of 60 ° C or higher. It provides a method for producing a thermoplastic resin composition excellent in weather resistance comprising a; 3rd step of blending a resin.

Hereinafter, the present invention will be described in detail.

(a-1) core-shell Graft  Copolymer

In the core-shell graft copolymer of the present invention, an aromatic vinyl compound and a vinyl cyan compound are grafted onto a conjugated diene-based rubber latex core to prepare a core-shell type.

The conjugated diene-based rubber latex core is preferably within the range of 200 to 500 nm in view of the physical properties such as impact, coloring and the like to secure the latex stability. In other words, if it is lower than 200 nm, physical properties are lowered, and if it is higher than 500 nm, latex stability is lowered and colorability is significantly lowered, which is not preferable.

As said aromatic vinyl compound, styrene derivatives, such as styrene or alpha-methylstyrene, para-methylstyrene, and vinyltoluene, can be used, and styrene is preferable. The content is preferably included in 25 to 50 parts by weight based on 100 parts by weight of the total core-shell graft copolymer.

As the vinyl cyan compound, acrylonitrile, methacrylonitrile, ethacrylonitrile, or the like may be used. Ethacrylonitrile is preferable in view of rigidity. The content is preferably included in 10 to 25 parts by weight based on 100 parts by weight of the total core-shell graft copolymer.

At this time, the additives usable include emulsifiers, initiators, activators, molecular weight regulators and the like. Examples of the emulsifier include, but are not limited to, oleic acid, stearic acid, lauric acid, fatty acid salt-based emulsifiers such as sodium or potassium salts of mixed fatty acids, or general anionic emulsifiers such as rosin acid, etc. It can be mixed and used.

As the initiator, an inorganic or organic peroxide compound may be used, and a water-soluble initiator including potassium persulfate, sodium persulfate, ammonium persulfate, or an oil-soluble initiator including cumene hydroperoxide, benzoyl peroxide, and the like may be used. have.

An activator may be used to promote the initiation reaction of the peroxide together with the initiator, and the activator may be one or two or more of sodium formaldehyde sulfoxylate, sodium ethylenediamine tetraacetate, ferrous sulfate or dextrose, and the like. It can be mixed and used.

As said molecular weight modifier, terpins, such as mercaptans, tabinolene, dipentene, and t-terpyene, or halogenated hydrocarbons, such as chloroform and carbon tetrachloride, can be used.

(a-2) hydrogenation Modified  Core-shell Graft  Copolymer

The core-shell graft copolymer prepared as described above is a technical feature of the present invention that is modified through a hydrogenation reaction.

That is, for the hydrogenation reaction, the core-shell graft copolymer is 0.1 to 100 parts by weight of hydrazine, 0.1 to 70 parts by weight of peroxide-based compound and 0.01 to 10 parts by weight of acid catalyst, based on 100 parts by weight of the copolymer in a latex state. Add.

In this case, hydrazine hydrate, hydrazine acetate, hydrazine sulfate, hydrazine hydrochloride and the like can be used, and preferably used in an amount of 0.1 to 100 parts by weight relative to 100 parts by weight of resin, more preferably 2 to 20 parts by weight. desirable. In this case, when the amount is less than 0.1 part by weight, the effect of improving weather resistance is poor, and when it exceeds 20 parts by weight, a gel is formed during the reaction, which may adversely affect the appearance characteristics, which is not preferable.

In addition, the peroxide-based compound usable may include hydroperoxide, and the like, in view of the efficiency of the hydrogenation reaction, it is preferable to use 0.1 to 70 parts by weight relative to 100 parts by weight of the resin, and use 2 to 20 parts by weight. It is more preferable to.

In addition, examples of the acid catalyst that can be used include, but are not limited to, boric acid, and the like. It is preferable to use 0.01-10 weight part with respect to 100 weight part of resin in consideration, and it is more preferable to use 0.2-2 weight part.

In addition, dimethylsiloxane (commercially available product name: siloxane) may be further added for the purpose of suppressing nitrogen gas generation during latex modification. In this case, the amount of use is preferably used in the range of 0.1 to 3 parts by weight based on 100 parts by weight of resin, which is undesirable because there is a possibility that the thermal stability is degraded when the excessive amount is added, and it may decompose during processing and adversely affect the surface properties.

According to the present invention, a reaction scheme in which a hydrogen and a hydroperoxide form a diimide, and the formed imide forms a double bond of butadiene as a single bond is as follows. As shown in the following scheme, nitrogen gas is produced during the process.

The core-shell graft copolymer modified in this manner was administered with an antioxidant and a stabilizer after the completion of the reaction, and then subjected to atmospheric aggregation using sulfuric acid or magnesium sulfate (MgSO ₄ ) as a flocculant, followed by dehydration, washing and drying to obtain a powder. It can be made into particles.

(b) Styrene Acrylonitrile  Suzy

The styrene-acrylonitrile resin used in the present invention is a hard matrix capable of melt kneading with a hydrogen-modified core-shell graft copolymer, and comprises a hard polymer having a glass transition temperature of at least 60 ° C., an aromatic vinyl compound, A compound containing a unit derived from a vinyl cyan compound, methyl methacrylate, or the like or a compound capable of forming a polycarbonate polymer is used alone or in combination of two or more thereof.

The styrene-acrylonitrile resin has an acrylonitrile content of 20 to 33%, more preferably 20 to 24%, a weight average molecular weight of 100,000 to 180,000, and two kinds of resins having a glass transition temperature of at least 60 ° C or higher. It is prepared by mixing.

The styrene-acrylonitrile resin has a weight average molecular weight of 100,000 to 120,000 and a total of 20 to 60 parts by weight of the first resin, which is a resin having high fluidity, and a high molecular weight second resin having a weight average molecular weight of 150,000 to 180,000. It can mix and use in the range which satisfy | fills -60 weight part. When two kinds of styrene-acrylonitrile resins are mixed and used in the composition as described above, appropriate fluidity and mechanical properties can be obtained.

At this time, if the glass transition temperature is too low, the physical properties such as stiffness are lowered, so 60 ° C is selected as the lower limit. In this case, the glass transition temperature of the first resin having high fluidity is 100 to 105 ° C, and the glass transition temperature of the high molecular weight second resin is more preferably 105 to 110 ° C.

In addition, the acrylonitrile content is preferably 20 to 33%. If the content is less than 20%, there is a problem that the chemical resistance is lowered, and when the content is more than 33%, fluidity and color are reduced, There is a problem that the color resistance is lowered due to the increase.

The thermoplastic resin composition of the present invention consists of 20 to 40 parts by weight of the hydrogenated modified core-shell graft copolymer of (a) and 60 to 80 parts by weight of the two styrene-acrylonitrile resins of (b). . If the hydrogenated modified core-shell graft copolymer content of (a) is less than 20 parts by weight, the impact resistance and weather resistance are lowered, whereas if it exceeds 40 parts by weight, gloss, scratch resistance and rigidity are deteriorated. Because.

It will be apparent to those skilled in the art that the thermoplastic resin composition of the present invention may further include a lubricant, a hindered phenol-based antioxidant, an ultraviolet stabilizer, an antistatic agent or other additives that are commonly used according to the use, in addition to the above components.

The lubricant may be ethylene bis stearamide, stearic acid, alkali metal stearate or low molecular weight polyethylene, etc. The lubricant may be included in an amount of 1 to 5 parts by weight based on 100 parts by weight of the resin.

The hindered phenolic antioxidants include stearyl-β- (3,5-di-t-butyl-4-hydroxyphenyl) and octadil-3- (4-hydroxy-3,5-di-tert- Butylphenyl) -propionate or 2,2-methylenebis (4-methyl-6-butylphenol) and the like, and the hindered phenolic antioxidant may be included in an amount of 0.1 to 0.5 parts by weight based on 100 parts by weight of the resin. Can be.

In addition, the phosphite-based antioxidant may be tris (2,4-di-t-butylphenyl) phosphite and the like, the phosphite-based antioxidant may be included in 0.1 to 0.5 parts by weight based on 100 parts by weight of the resin. .

The sunscreen may be used at the same time usually two kinds, especially as a UV stabilizer, bis (2,2,6,6-tetramethyl-4-piperidinyl) or 2- (2-hydroxy-5-methylphenyl) Benzotriazole may be used, and the UV stabilizer may be included in an amount of 0.1 to 0.5 parts by weight based on 100 parts by weight of the resin.

In addition, as a UV absorber which is a kind of ultraviolet ray inhibitor, 0.1 to 0.5 weight of 2- (5-chloro-2-benzotriazole) -4,6-bis (1,1-dimethylethyl) phenol based on 100 parts by weight of the resin It is preferable to be contained by the part.

The above-mentioned thermoplastic resin composition may melt knead all the components such as the core-shell graft copolymer of a) and the styrene-acrylonitrile resin of b) at the same time, or optionally add the remaining components to the composition kneaded with one component. It can be manufactured by melt kneading. Specifically, the manufacturing method is as follows:

In a first step, a core-shell graft copolymer is prepared by grafting an aromatic vinyl compound and a vinyl cyan compound on a conjugated diene rubber latex core having an average particle diameter of 200 to 500 nm.

For example, as shown in the following examples, 30 parts by weight of styrene and 10 parts of acrylonitrile using rosin acid and cumene hydroperoxide in 60 parts by weight of butadiene polymer having an average rubber particle diameter of 200 to 500 nm. Copolymer latex with grafted portions can be prepared.

Then, as a second step, 0.1 to 100 parts by weight of hydrazine, 0.1 to 70 parts by weight of peroxide-based compound and 0.01 to 10 parts by weight of acid catalyst, based on 100 parts by weight of the copolymer in the latex state in the core-shell graft copolymer And hydrogenated modified core-shell graft copolymer.

In particular, the hydrogenation reforming process is preferably carried out in the range of 250 to 300 rpm for 1 to 3 hours at 50 to 80 ℃, dimethylsiloxane relative to 100 parts by weight of the copolymer in order to suppress the generation of nitrogen in the hydrogenation reforming It can be used together in the range of 0.1 to 3 parts by weight.

Specifically, as identified in the Examples, 1 part by weight of hydrazine hydrate was mixed at 100 parts by weight of the prepared copolymer latex at 50 to 80 ° C., then 0.7 part by weight of hydroperoxide and 0.07 part by weight of boric acid were 250 at 70 ° C. After reacting with stirring for 1 to 3 hours while stirring at -300 rpm, the mixture is agglomerated to obtain modified core-shell graft copolymer powder particles.

In addition, batchwise addition is also possible, that is, 1 part by weight of hydrazine hydrate is mixed with 100 parts by weight of copolymer latex at 70 ° C., 0.7 parts by weight of hydroperoxide and 0.07 parts by weight of boric acid are added in a batch under 270 rpm. Aggregation may be achieved by stirring for a time.

In addition, 1 part by weight of hydrazine hydrate and 0.2 parts by weight of siloxane were mixed at 100 parts by weight of the copolymer latex at 70 ° C., and then 0.7 parts by weight of hydroperoxide and 0.07 parts by weight of boric acid were added at 270 rpm, followed by stirring for 1 hour. It may be aggregated, 2 parts by weight of hydrazine hydrate, 0.4 parts by weight of siloxane, 1.5 parts by weight of hydroperoxide and 0.15 parts by weight of boric acid at 100 parts by weight of copolymer latex at 70 ° C. under 270 rpm, followed by stirring for 1 hour. It can also be made to aggregate.

Then, an antioxidant and a sunscreen may be further added to the modified copolymer prior to the third step.

After the third step, the modified core-shell graft copolymer 20 to 40 parts by weight of acrylonitrile content of 20 to 33%, weight average molecular weight of 100,000 to 180,000, two glass transition temperature of 60 ℃ or more Styrene-acrylonitrile resin of is mix | blended as remainder.

Simultaneously or sequentially with the third step, one or more additives selected from the group consisting of lubricants, hindered phenolic antioxidants, anti-UV agents, UV absorbers and antistatic agents may be further added.

Specifically, 30 parts by weight of the modified core-shell graft copolymer powder and a high-strength SAN resin having an acrylonitrile content of 24% as a hard matrix, a weight average molecular weight of 100,000 to 120,000, and a glass transition temperature of 100 to 105 ° C. 35 parts by weight, and 100 parts by weight of a base resin composed of 70 parts by weight of a SAN resin composed of 35 parts by weight of a high molecular weight SAN resin having an acrylonitrile content of 24%, a weight average molecular weight of 150,000 to 180,000, and a glass transition temperature of 105 to 110 ° C. 1.0 part by weight of ethylene bis stearamide as a lubricant, 0.5 part by weight of stearyl-β- (3,5-di-t-butyl-4-hydroxyphenyl) as a hindered phenolic antioxidant, Tris as a phosphite antioxidant 0.5 part by weight of (2,4-di-t-butylphenyl) phosphite, 0.3 part by weight of bis (2,2,6,6-tetramethyl-4-piperidinyl) as a UV stabilizer and 2- (2-hydride) 0.3 parts by weight of oxy-5-methyl phenyl) benzotriazole was added and mixed To obtain a resin composition.

The thermoplastic resin composition thus obtained is prepared in pellet form using an extruder kneader at a cylinder temperature of 220 ° C., and the specimen is injected into the pellet to prepare a specimen. The weather resistance is remarkably maintained while maintaining the Izod impact strength, the tensile strength, and the bending strength. To obtain an improved thermoplastic resin.

The thermoplastic resin obtained according to the present invention has not only impact resistance and rigidity but also excellent weather resistance, so that the thermoplastic resin can be used as exterior materials, automobile parts, electric-electronic parts or building materials.

According to the present invention, in a resin consisting of two kinds of SAN resins having different grafted ABS resins and weight average molecular weights, the grafted ABS is modified and used by a hydrogenation reaction so that impact resistance, rigidity and weather resistance can be achieved by a simple process. There is an effect of providing an excellent thermoplastic resin composition.

Example  One

Example  1-1: core-shell Graft  Copolymer production

A copolymer (g-ABS) latex was prepared by grafting 30 parts by weight of styrene and 10 parts by weight of acrylonitrile using rosin acid and cumene hydroperoxide to 60 parts by weight of butadiene polymer having an average rubber particle diameter of 300 nm. .

Example  1-2: latex modification

1 part by weight of hydrazine hydrate was mixed with 100 parts by weight of the prepared core-shell graft copolymer latex at 70 ° C., followed by stirring at 0.7 parts by weight of hydroperoxide and 0.07 parts by weight of boric acid at 270 rpm for 1 hour while maintaining the temperature. After reacting with Increment, the mixture was aggregated to obtain modified graft copolymer powder particles.

Example  1-3: Preparation of the thermoplastic resin composition

30 parts by weight of modified graft copolymer powder and a hard matrix high acrylonitrile content of 24%, a weight average molecular weight of 100,000 and a glass transition temperature of 100 to 105 ° C (LG Chemical Co., Ltd., product name '80HF) SAN) consisting of 35 parts by weight, and 35 parts by weight of a high molecular weight SAN resin (manufactured by LG Chemical, product name '92HR') having an acrylonitrile content of 24%, a weight average molecular weight of 150,000 and a glass transition temperature of 105 to 110 ° C. 1.0 part by weight of ethylene bisstearoamide as a lubricant, 100 parts by weight of a base resin of 70 parts by weight of resin, and a stearyl-β- (3,5-di-t-butyl-4-hydroxyphenyl as a hindered phenol-based antioxidant 0.5 part by weight of tris (2,4-di-t-butylphenyl) phosphite as a phosphite antioxidant, and bis (2,2,6,6-tetramethyl-4-piperidinyl as a UV stabilizer ) 0.3 part by weight and 0.3 part by weight of 2- (2-hydroxy-5-methyl phenyl) benzotriazole It was mixed to prepare a thermoplastic resin composition.

Example  1-4: Manufacture of thermoplastic resin

The thermoplastic resin composition was prepared in pellet form using an extruder kneader (manufactured by ENGEL, under 150 rpm) at a cylinder temperature of 220 ° C., and was injected into the pellet to produce Izod impact strength, tensile strength, and flexural strength. , The weather resistance was measured and the results obtained are summarized together in Table 1 below.

Example  2

The same procedure as in Example 1 was repeated except that the hydroperoxide and boric acid were added as a batch in the latex modification process of Example 1-2, followed by stirring for 1 hour. , Tensile strength, flexural strength, weather resistance were measured and the results obtained are summarized together in Table 1 below.

Example  3

Izod impact strength, tensile strength, flexural strength with the specimen obtained by repeating the same process as in Example 1, except that 0.2 parts by weight of siloxane was stirred together when the hydrazine hydrate was stirred in the latex modification process of Example 1-2. , The weather resistance was measured and the results obtained are summarized together in Table 1 below.

Example  4

The same process as in Example 1 except that 2 parts by weight of hydrazine hydrate, 0.4 parts by weight of siloxane, 1.5 parts by weight of hydroperoxide and 0.15 parts by weight of boric acid were added together in the latex modification process of Example 1-2. Izod impact strength, tensile strength, flexural strength and weather resistance were measured with the specimens obtained by repeating the above, and the results obtained are summarized together in Table 1 below.

Comparative example  1: latex Reforming process  If not done

Except for the latex modification process of Example 1-2, Izod impact strength, tensile strength, flexural strength, and weather resistance were obtained by measuring the specimens in the order of Examples 1-1, 1-3, and 1-4 in order. The results are summarized together in Table 1 below.

Comparative example  2: latex Reforming Process  without Phosphite  When adding antioxidants and phosphates

A copolymer latex of 30 parts by weight of styrene and 10 parts by weight of acrylonitrile was prepared by aggregating rosin acid and cumene hydroperoxide with 60 parts by weight of butadiene polymer having an average rubber particle diameter of 300 nm, and then coagulating the core-shell graph. Copolymer powder particles were obtained.

30 parts by weight of the graft copolymer powder obtained above and an acrylonitrile content of 24% as a hard matrix and a weight average molecular weight of 100,000 SAN resin composed of 35 parts by weight of a high flow SAN resin having a glass transition temperature of 100 to 105 ° C., and 35 parts by weight of a high molecular weight SAN resin having an acrylonitrile content of 24%, a weight average molecular weight of 150,000 and a glass transition temperature of 105 to 110 ° C. 100 parts by weight of the base resin consisting of 70 parts by weight of ethylene bisstearoamide 2.0 parts by weight of lubricant, 0.3 parts by weight of 2,2-methylenebis (4-methyl-6-butylphenol) as a hindered phenolic antioxidant, 0.25 parts by weight of bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite as a distearyl pentaerythritol diphosphite as a phosphite antioxidant and a second phosphite antioxidant as sodium phosphate as an alkali metal phosphate 0.05 parts by weight of pite and 0.25 parts by weight of bis (2,2,6,6, -tetramethyl-4-piperidinyl) as a UV stabilizer and 2- (5-chloro-2-benzotriazole) -4,6- 0.25 parts by weight of bis (1,1-dimethylethyl) phenol was added and mixed A thermoplastic resin composition was prepared.

The thermoplastic resin composition was prepared in pellet form using a 40 pie extrusion kneader at a cylinder temperature of 220 ° C., injected into the pellet to prepare a specimen, and the physical properties thereof were shown in Table 1 below.

Comparative example  3: latex Without modification High flow  Styrene Acrylonitrile  When using only resin

In Comparative Example 2, the results obtained in the same manner as in Comparative Example 2 were summarized together in Table 1, except that 70 parts by weight of the first SAN resin having a high average molecular weight of 100,000 was used alone.

The physical properties of the thermoplastic resin composition specimens prepared in Examples 1-4 and Comparative Examples 1-3 were measured by the following method.

Property measurement method:

A) Izod impact strength (notched 1/4 "at 23 ° C., kg · cm / cm) —measured according to ASTM D256.

B) Tensile strength (50 mm / min, kg / cm 2)-measured according to ASTM D638.

C) Flexural strength (15 mm / min, kg / cm 2)-measured according to ASTM D790.

Weather resistance-UV accelerated test, 0.55 W / ㎡, 600 hours test using the Atlas UV2000 machine, using a colorimeter to measure the color change of the test specimen by △ E. Smaller values of DELTA E indicate less discoloration and better weatherability.

Classification Example Comparative example One 2 3 4 One 2 3 Impact strength 31.80 30.80 31.71 31.71 31.62 31 27 The tensile strength 536 532 536 535 533 521 490 Flexural strength 990 954 966 964 988 890 898 Weather resistance ( △ E ) 3.5 4 3.7 2.8 7 3.9 3.7

As shown in Table 1, the thermoplastic resin composition of Examples 1 to 4 including a latex modified by the hydrogenation reaction according to the present invention in an appropriate content range is weather resistance without lowering impact strength, tensile strength and flexural strength Is significantly improved, but when the hydrogenation reaction is not performed (Comparative Example 1), the weather resistance is remarkably decreased, and when a stabilizer or the like is used (Comparative Example 2), the weather resistance is improved, but the mechanical properties of the resin itself are reduced, and the high-flow styrene- When acrylonitrile resin was used alone (Comparative Example 3), it was confirmed that mechanical properties such as impact physical properties were lowered.

Although described in detail above with reference to the specific embodiments of the present invention, various changes and modifications within the scope and spirit of the present invention will be apparent to those skilled in the art, such variations and modifications belong to the appended claims It is also natural.

Claims (13)

a) A hydrazine, a peroxide compound and an acid catalyst are added to a core-shell graft copolymer in which an aromatic vinyl compound and a vinyl cyan compound are grafted to a conjugated diene rubber latex core having an average particle diameter of 200 to 500 nm, and hydrogen 20 to 40 parts by weight of the addition modified core-shell graft copolymer, and b) a thermoplastic composition comprising 60 to 80 parts by weight of two styrene-acrylonitrile resins having an acrylonitrile content of 20 to 33%, a weight average molecular weight in the range of 100,000 to 180,000, and a glass transition temperature of 60 ° C or higher. Resin composition. The method of claim 1, The a) hydrazine, peroxide-based compound and acid catalyst ranges from 0.1 to 100 parts by weight of hydrazine, 0.1 to 70 parts by weight of peroxide compound and 0.01 to 10 parts by weight of acid catalyst based on 100 parts by weight of the core-shell graft copolymer. A thermoplastic resin composition having excellent weather resistance, characterized by being used internally. The method according to claim 1 or 2, Furthermore, the (a) core-shell graft copolymer further comprises dimethylsiloxane in the range of 0.1 to 3 parts by weight based on 100 parts by weight of the copolymer. The method according to claim 1 or 2, The hydrazine is a thermoplastic resin composition excellent in weather resistance, characterized in that selected from hydrazine hydrate, hydrazine acetate, hydrazine sulfate, or hydrazine hydrochloride. The method of claim 1, The peroxide-based compound is a thermoplastic resin composition excellent in weatherability, characterized in that the hydroperoxide. The method of claim 1, The acid catalyst is a thermoplastic resin composition excellent in weatherability, characterized in that using boric acid. The method of claim 1, The (b) two styrene-acrylate resins (b-1) 20 to 60 parts by weight of the first styrene-acrylate resin having an acrylonitrile content of 20 to 33%, a weight average molecular weight of 100,000 to 120,000, and a glass transition temperature of 100 to 105 ° C; And (b-2) 20 to 60 parts by weight of a second styrene-acrylate resin having an acrylonitrile content of 20 to 33%, a weight average molecular weight of 150,000 to 180,000, and a glass transition temperature of 105 to 110 ° C; Thermoplastic resin composition excellent in weatherability, characterized in that consisting of. The method of claim 1, The thermoplastic resin composition further comprises at least one additive selected from the group consisting of lubricants, hindered phenolic antioxidants, phosphite antioxidants, ultraviolet stabilizers, UV absorbers and antistatic agents. Thermoplastic resin composition. The method of claim 8, The additive is based on 100 parts by weight of the thermoplastic resin composition 1 to 5 parts by weight of lubricant, 0.1 to 0.5 parts by weight of hindered phenolic antioxidant, 0.1 to 0.5 parts by weight of phosphite antioxidant, 0.1 to 0.5 parts by weight of UV stabilizer, UV A thermoplastic resin composition having excellent weather resistance, characterized in that it is used within the range of 0.1 to 0.5 parts by weight of the absorbent. A first step of preparing a core-shell graft copolymer in which an aromatic vinyl compound and a vinyl cyan compound are grafted to a conjugated diene rubber latex core having an average particle diameter of 200 to 500 nm; Adding a hydrazine, a peroxide-based compound and an acid catalyst to the core-shell graft copolymer to obtain a hydrogenated core-shell graft copolymer; And 20 parts by weight of the hydrogenated modified core-shell graft copolymer, and two styrenes having an acrylonitrile content of 20 to 33%, a weight average molecular weight in the range of 100,000 to 180,000, and a glass transition temperature of 60 ° C or higher. A third step of blending 60 to 80 parts by weight of acrylonitrile resin; Thermoplastic resin composition excellent in weather resistance comprising a. The method of claim 10, The hydrazine, peroxide-based compound and acid catalyst is used within the range of 0.1 to 100 parts by weight of hydrazine, 0.1 to 70 parts by weight of peroxide compound and 0.01 to 10 parts by weight of acid catalyst based on 100 parts by weight of the core-shell graft copolymer. Thermoplastic resin composition excellent in weatherability, characterized by the above-mentioned. The method of claim 11, Furthermore, the thermoplastic resin composition having excellent weather resistance, further comprising dimethylsiloxane in the range of 0.1 to 3 parts by weight based on 100 parts by weight of the core-shell graft copolymer. The method of claim 10, The hydrogenation reforming process of the second step is a method for producing a thermoplastic resin composition excellent in weather resistance, characterized in that carried out in 50 to 80 ℃ for 1 to 3 hours in the range of 250 to 300 rpm.